It is possible for Arduino-like boards to pass audio over USB (input and output). Arduino Mbed natively supports this. A raspberry pi pico can both get audio from a computer and convert it to analog using PWM or PDM. I've written a library to perform 64-times oversampling with a 4th order modulator on the pico for USB audio streaming and digital to analog conversion. However I am unsure how you would
I'm not sure that is possible even with multiple devices (but maybe someone has done it). For instance, if you play two different songs on your computer they end up digitally mixed on the USB streamer. You never get two separate streams.